US5006956A - Dielectric ceramic composition - Google Patents

Dielectric ceramic composition Download PDF

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Publication number
US5006956A
US5006956A US07/432,880 US43288089A US5006956A US 5006956 A US5006956 A US 5006956A US 43288089 A US43288089 A US 43288089A US 5006956 A US5006956 A US 5006956A
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United States
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sub
mol
amount
dielectric
represented
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US07/432,880
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English (en)
Inventor
Kouji Kawakita
Suzushi Kimura
Hideyuki Orinaka
Youichiro Yokotani
Mariko Ishikawa
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Panasonic Holdings Corp
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Matsushita Electric Industrial Co Ltd
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Priority claimed from JP63280812A external-priority patent/JP2523834B2/ja
Priority claimed from JP1029088A external-priority patent/JP2797370B2/ja
Application filed by Matsushita Electric Industrial Co Ltd filed Critical Matsushita Electric Industrial Co Ltd
Assigned to MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD. reassignment MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: ISHIKAWA, MARIKO, KAWAKITA, KOUJI, KIMURA, SUZUSHI, OKINAKA, HIDEYUKI, YOKOTANI, YOUICHIRO
Priority to US07/649,463 priority Critical patent/US5093757A/en
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    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
    • C04B35/46—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on titanium oxides or titanates
    • C04B35/462—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on titanium oxides or titanates based on titanates
    • C04B35/472—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on titanium oxides or titanates based on titanates based on lead titanates
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
    • C04B35/495—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on vanadium, niobium, tantalum, molybdenum or tungsten oxides or solid solutions thereof with other oxides, e.g. vanadates, niobates, tantalates, molybdates or tungstates
    • C04B35/497—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on vanadium, niobium, tantalum, molybdenum or tungsten oxides or solid solutions thereof with other oxides, e.g. vanadates, niobates, tantalates, molybdates or tungstates based on solid solutions with lead oxides
    • C04B35/499—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on vanadium, niobium, tantalum, molybdenum or tungsten oxides or solid solutions thereof with other oxides, e.g. vanadates, niobates, tantalates, molybdates or tungstates based on solid solutions with lead oxides containing also titanates
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G4/00—Fixed capacitors; Processes of their manufacture
    • H01G4/002—Details
    • H01G4/018—Dielectrics
    • H01G4/06—Solid dielectrics
    • H01G4/08—Inorganic dielectrics
    • H01G4/12—Ceramic dielectrics
    • H01G4/1209—Ceramic dielectrics characterised by the ceramic dielectric material
    • H01G4/1254—Ceramic dielectrics characterised by the ceramic dielectric material based on niobium or tungsteen, tantalum oxides or niobates, tantalates

Definitions

  • the present invention relates to a dielectric ceramic composition exhibiting a high dielectric constant, capable of sintering in a short time, at a sintering temperature of 800° to 1000° C., in the atmosphere, a neutral atmosphere or a reducing atmosphere.
  • One method involves making barium titanate material resistive to reduction, and sintering it in an atmosphere of a low oxygen partial pressure, thus making it possible to use an inexpensive base metal as the electrode material.
  • the other method involves sintering at a low temperature of about 1000° C. a silver-palladium alloy electrode material and a lead dielectric material and inexpensive silver.
  • the hybrid IC of a high packaging density is promoted, and the demand for a thick film capacitor is mounting to replace the conventional chip capacitor.
  • a dielectric material capable of sintering at a low temperature and in a short time is required, and the lead dielectric is used mainly as this material. Therefore, as the material applicable to both increasing the capacity of a laminate chip capacitor and providing a thick film capacitor, the lead dielectric is being developed intensively.
  • a PbTiO 3 - Pb(Mg 1/3 Nb 2/3 )O 3 - Pb(Ni 1/2 W 1/2 )O 3 solid solution and a PbZrO 3 - Pb(Ni 1/3 Nb 2/3 )O 3 - Pb(Ni 1/2 Wi1/2)O 3 solid solution are compositions exhibiting a high dielectric constant which can be sintered in the atmosphere at 1100° C. or a lower temperature, as disclosed in Japanese Patent Laid-Open Nos. 61-155249 and No. 61-155248, but it is necessary to maintain the sintering temperature for several hours in order to heighten the dielectric constant and to obtain sintered material having a sufficient density.
  • a primary object of the present invention to provide a dielectric ceramic composition exhibiting a high dielectric constant, and a ceramic capacitor or thick film capacitor using the same, capable of sintering at 800° to 1000° C. in a short time in the atmosphere, a neutral atmosphere or a reducing atmosphere, without detrimentally affecting the high dielectric constant of a PbTiO 3 - Pb(Mg 1/3 Nb 2/3 )O 3 - Pb(Ni 1/2 W 1/2 )O 3 solid solution and a PbZrO 3 - Pb(Ni 1/3 Nb 2/3 )O 3 - Pb(Ni 1/2 Wi 1/2 )O 3 solid solution.
  • the present invention provides a dielectric ceramic composition
  • the subsidiary components are added to the calcined powder of the main components represented by the formula PbTi x (Mg 1/3 Nb 2/3 ) y (Ni1/2 W 1/2 ) z O 3 .
  • the polygon ABCDE shows a range of composition of the ceramic composition of the present invention, and the compositions A, B, C, D, E at the vertices of the polygon are expressed by the following numerical values: ##EQU1##
  • the present invention provides a dielectric ceramic composition
  • the subsidiary components are added to the calcined powder of the main components represented by the formula PbZr x Nb 2/3 ) y (Ni 1/2 W 1/2 ) z O 3 .
  • the polygon ABCD shows a range of composition of the ceramic composition of the present invention, and the compositions A, B, C, and D at the vertices of the polygon are expressed by the following numerical values: ##EQU2##
  • the dielectric ceramic composition of the invention by adding PbO and NiO or Wo 3 to the calcined powder of PbTiO 3 - Pb(Mg 1/3 Nb 2/3 )O 3 -Pb(Ni 1/2 W 1/2 )O 3 system and PbZrO 3 - Pb(Ni 1/3 Nb 2/3 )O 3 -Pb(Ni 1/2 W 1/2 )O 3 system having the perovskite structure, a liquid phase is generated at low temperature by making use of the eutectic composition of PbO and NiO, or PbO and WO 3 , and when these additives are simultaneously solubilized at site A and site B, diffusion into the dielectric is smooth, and formation of a grain boundary layer due to additives is suppressed.
  • FIG. 1 is a ternary system composition diagram mainly composed of PbTiO 3 , Pb(Mg 1/3 Nb 2/3 )O 3 and Pb(Ni 1/2 W 1/2 )O 3 showing the composition range of one of the embodiments of the invention, and
  • FIG. 2 is a ternary system composition diagram mainly composed of PbZrO 3 , Pb(Ni 1/3 Nb 2/3 )O 3 and PB(Ni 1/2 W 1/2 )O 3 showing the composition range of the other embodiment of the invention.
  • PbO, MgO, Nb 2 O 5 , TiO 2 , NiO, and WO 3 of chemically high purity were used. After correcting their purity, specified amounts were weighed, and purified water was added, and then mixed in a ball mill for 17 hours using agate balls. After separating the majority of water content by suction filtration, the residue was dried, sufficiently crushed by an automatic agate mortar, and 5 wt. % of the powder of purified water was added, and the powder was formed into a columnar shape of 60 mm in diameter and about 50 mm in height at a forming pressure of 500 kg/cm 2 .
  • Table 1 shows the material composition of the invention and the dielectric characteristics of the specimens sintered in the atmosphere. The results were of 900° C. sintered in the sintering atmosphere of a neutral atmosphere of nitrogen, and in a nitrogen-hydrogen mixed gas with an oxygen partial pressure of 10 -8 atm or more are shown in Tables 2 and 3, respectively.
  • FIG. 1 the composition range of the principal components of the invention are shown in the ternary system composition diagram mainly composed of PbTiO 3 , Pb(Mg 1/3 Nb 2/3 )O 3 and Pb(Ni 1/2 W 1/2 )O 3 .
  • the subsidiary components are added to the calcined powder of the main components represented by the formula PbTi x (Mg 1/3 Nb2/3) y (Ni 178 W 1/2 ) z O 3 .
  • the polygon ABCDE shows a range of composition of the ceramic composition of the present invention, and the compositions A, B, C, D, E at the vertices of the polygon are expressed by the following numerical values: ##EQU3##
  • the sintering is insufficient in a composition outside the specified range, as indicated by the reference examples shown in Tables 1 to 3, since the dielectric constant of the sintered materials at a sintering temperature of 900° C. is less than 5000. Furthermore, at a sintering temperature of 800° C. or less, the sintering is insufficient, and at 1000° C. or higher, the dielectric constant is lowered, and desired characteristics may not be obtained.
  • the dielectric constant of the sinters are less than 5000 at a sintering temperature of 800° to 1000° C., and the sintering is insufficient, in compositions other than those in the defined range of the present invention as indicated by the reference examples in Table 4.
  • any electrodes that can be sintered at 800 to 1000° C. in the atmosphere, a neutral atmosphere or a reducing atmosphere may be properly selected and used.
  • the thus obtained sintered piece was processed into a disk of 1 mm in thickness, C-Au was evaporated on both sides as the electrodes, and the dielectric constant and tan ⁇ were measured in an electric field of 1 kHz, 1 V/mm.
  • Table 5 shows the material composition of the invention and the dielectric characteristics of the specimens sintered in the atmosphere. The results of 900° C. sintering in the sintering atmosphere of a neutral atmosphere of nitrogen, and in a nitrogen-hydrogen mixed gas with the oxygen particle pressure of 10 -8 atm or more are shown in Tables 6 and 7, respectively.
  • composition range of the principal components of the invention is shown in the ternary system composition diagram mainly composed of PbZrO 3 , Pb(Ni 1/3 Nb 2/3 )O 3 and Pb(Ni 1/2 W 1/2 )O 3 .
  • the subsidiary components are added to the calcined powder of the main components represented by the formula PbZr x (Ni 1/3 Nb 2/3 ) y (Ni 1/2 W 1/2 ) z O 3 .
  • the polygon ABCD shows a range of composition of the ceramic composition of the present invention
  • the compositions A, B, C, and D at the vertices of the polygon are expressed by the following numerical values: ##EQU4## is that the sintering is insufficient and the dielectric constant of the sinters which are sintered at a sintering temperature of 900° C. is less than 5000 in a composition outside the specified range as indicated by reference examples shown in Tables 5 to 7. Furthermore, at sintering temperature of 800° C. or less, the sintering is insufficient, and at 1000° C. or higher, the dielectric constant is lowered, and desired characteristics may not be obtained.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Ceramic Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Organic Chemistry (AREA)
  • Structural Engineering (AREA)
  • Materials Engineering (AREA)
  • Power Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Inorganic Insulating Materials (AREA)
  • Ceramic Capacitors (AREA)
  • Compositions Of Oxide Ceramics (AREA)
US07/432,880 1988-11-07 1989-11-07 Dielectric ceramic composition Expired - Lifetime US5006956A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US07/649,463 US5093757A (en) 1988-11-07 1991-02-05 Dielectric ceramic composition

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP63-280812 1988-11-07
JP63280812A JP2523834B2 (ja) 1988-11-07 1988-11-07 高誘電率系誘電体磁器組成物
JP1-29088 1989-02-08
JP1029088A JP2797370B2 (ja) 1989-02-08 1989-02-08 高誘電率系誘電体磁器組成物

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EP (1) EP0368619B1 (de)
DE (1) DE68926099T2 (de)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5106796A (en) * 1991-09-13 1992-04-21 E. I. Du Pont De Nemours And Company Low-firing capacitors dielectrics
US5135897A (en) * 1990-02-22 1992-08-04 Mitsubishi Materials Corporation Electro-optical effect composition
US5304967A (en) * 1991-02-05 1994-04-19 Tdk Corporation Multi-layer circuit board dielectric filter having a plurality of dielectric resonators
US5337209A (en) * 1992-09-10 1994-08-09 Martin Marietta Corporation High energy density lead magnesium niobate-based dielectric ceramic and process for the preparation thereof
US5759934A (en) * 1996-03-26 1998-06-02 Murata Manufacturing Co., Ltd. Dielectric ceramic composition
US6137672A (en) * 1997-02-10 2000-10-24 Taiyo Yuden Co., Ltd. Laminated electronic part, method for the production thereof, and dielectric ceramic composition
US20020024080A1 (en) * 2000-08-31 2002-02-28 Derderian Garo J. Capacitor fabrication methods and capacitor constructions
US20020094632A1 (en) * 2000-08-31 2002-07-18 Agarwal Vishnu K. Capacitor fabrication methods and capacitor constructions
US6652905B2 (en) * 2000-09-20 2003-11-25 Ngk Insulators, Ltd. Piezoelectric element and process for production thereof
US20050269669A1 (en) * 2003-07-21 2005-12-08 Mcclure Brent A Capacitor constructions and methods of forming
US20080239627A1 (en) * 2007-03-27 2008-10-02 Keith Bridger High-Temperature Dielectric Materials and Capacitors Made Therefrom

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02170583A (ja) * 1988-12-23 1990-07-02 Taiyo Yuden Co Ltd 圧電性磁器およびその製造方法

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4711862A (en) * 1984-12-27 1987-12-08 Matsushita Electric Industrial Co., Ltd. Dielectric ceramic compositions

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61256959A (ja) * 1985-05-02 1986-11-14 ティーディーケイ株式会社 高誘電率磁器組成物
US4772985A (en) * 1986-09-24 1988-09-20 Kabushiki Kaisha Toshiba Thick film capacitor

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4711862A (en) * 1984-12-27 1987-12-08 Matsushita Electric Industrial Co., Ltd. Dielectric ceramic compositions

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
Guha et al., Effect of Excess PbO on the Sintering Characteristics and Dielectric Properties of Pb(Mg 1/3 Nb 2/3 )O 3 PbTiO 3 Based Ceramics, J. Am. Ceramic Society, Mar. 1988. *
Guha et al., Effect of Excess PbO on the Sintering Characteristics and Dielectric Properties of Pb(Mg1/3 Nb2/3)O3 PbTiO3 -Based Ceramics, J. Am. Ceramic Society, Mar. 1988.

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5135897A (en) * 1990-02-22 1992-08-04 Mitsubishi Materials Corporation Electro-optical effect composition
US5304967A (en) * 1991-02-05 1994-04-19 Tdk Corporation Multi-layer circuit board dielectric filter having a plurality of dielectric resonators
US5106796A (en) * 1991-09-13 1992-04-21 E. I. Du Pont De Nemours And Company Low-firing capacitors dielectrics
US5337209A (en) * 1992-09-10 1994-08-09 Martin Marietta Corporation High energy density lead magnesium niobate-based dielectric ceramic and process for the preparation thereof
US5759934A (en) * 1996-03-26 1998-06-02 Murata Manufacturing Co., Ltd. Dielectric ceramic composition
US6137672A (en) * 1997-02-10 2000-10-24 Taiyo Yuden Co., Ltd. Laminated electronic part, method for the production thereof, and dielectric ceramic composition
US20070007572A1 (en) * 2000-08-31 2007-01-11 Agarwal Vishnu K Capacitor fabrication methods and capacitor constructions
US20020094632A1 (en) * 2000-08-31 2002-07-18 Agarwal Vishnu K. Capacitor fabrication methods and capacitor constructions
US7109542B2 (en) 2000-08-31 2006-09-19 Micron Technology, Inc. Capacitor constructions having a conductive layer
US7112503B1 (en) 2000-08-31 2006-09-26 Micron Technology, Inc. Enhanced surface area capacitor fabrication methods
US20020024080A1 (en) * 2000-08-31 2002-02-28 Derderian Garo J. Capacitor fabrication methods and capacitor constructions
US7217615B1 (en) 2000-08-31 2007-05-15 Micron Technology, Inc. Capacitor fabrication methods including forming a conductive layer
US20070178640A1 (en) * 2000-08-31 2007-08-02 Derderian Garo J Capacitor fabrication methods and capacitor constructions
US7288808B2 (en) * 2000-08-31 2007-10-30 Micron Technology, Inc. Capacitor constructions with enhanced surface area
US6652905B2 (en) * 2000-09-20 2003-11-25 Ngk Insulators, Ltd. Piezoelectric element and process for production thereof
US20050269669A1 (en) * 2003-07-21 2005-12-08 Mcclure Brent A Capacitor constructions and methods of forming
US7440255B2 (en) 2003-07-21 2008-10-21 Micron Technology, Inc. Capacitor constructions and methods of forming
US20080239627A1 (en) * 2007-03-27 2008-10-02 Keith Bridger High-Temperature Dielectric Materials and Capacitors Made Therefrom
US7697263B2 (en) * 2007-03-27 2010-04-13 Active Signal Technologies, Inc. High-temperature dielectric materials and capacitors made therefrom

Also Published As

Publication number Publication date
EP0368619B1 (de) 1996-03-27
EP0368619A1 (de) 1990-05-16
DE68926099T2 (de) 1996-10-10
DE68926099D1 (de) 1996-05-02

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